Card-linked loyalty for UK merchants
A plain guide for UK shops, cafés and restaurants: what card-linked loyalty is, how it compares with card-linked offers and app loyalty, and how privacy and set-up work.
Card-linked loyalty is a loyalty programme where customers earn rewards from the payment card they already use. There is no separate loyalty card, app or QR code to show.
For a shop, café or restaurant, that means your card machine does the work: a customer joins once, then later card payments can count towards their reward. This guide explains how it works, how it differs from card-linked offers and app-based loyalty, and what it means for privacy, refunds and your day-to-day running.
Updated 9 November 2026. If you are a payment provider, read our technical guide to card-linked loyalty for payment providers instead.
How card-linked loyalty works
At a plain level, there are three moments:
- The customer joins once. With Zeal, a new customer can join in a couple of taps on the card machine screen, without downloading anything or giving an email address.
- They pay as normal. On later visits, Zeal recognises returning customers from the card they pay with. Recognition happens as part of the transaction, so the payment proceeds as it does today.
- They earn during the payment. Points, stamps or vouchers are awarded while the payment completes, and the customer sees their balance or reward on the card machine. It can print on the receipt too.
Nothing is added to the payment your staff take. Nobody has to remember to ask "do you have a loyalty card?", and the experience is the same on a quiet Tuesday as on a busy Saturday.
You may also hear the closely related term payment-linked loyalty. Many people use the two interchangeably: the payment is how the customer is recognised and how they earn.
Card-linked loyalty compared with other kinds of loyalty
"Card-linked" is used for two quite different things, and both are different again from app or stamp-card loyalty. Here is how they compare for a merchant.
| Card-linked loyalty on your card machine | Card-linked offers | App, QR or stamp-card loyalty | |
|---|---|---|---|
| Who runs it | You, with software on your card machine | A bank, card company or cashback app | You, often with a loyalty software provider |
| How customers join | On your card machine, during a payment | In the bank's or app's own service, before they shop | Download an app, add a wallet pass or take a paper card |
| What customers do each visit | Pay as normal | Pay with the card the offer is saved to | Show or scan a code, or get a stamp |
| Whose programme it is | Yours, in your brand | The bank's or app's, across many retailers | Yours |
| Reaches cash customers? | No | No | Yes, if they take part |
Card-linked offers
Card-linked offers are deals that a bank, card company or cashback app shows its own customers. The customer saves the offer to their card before they shop, and the reward arrives later from the scheme. American Express, for example, tells UK cardholders "You must save the offer to your Card first", then pay with that same card.
These schemes can put your business in front of a bank's or app's audience. But the programme belongs to the scheme, the customer joined with the scheme rather than with you, and your offer sits alongside many other retailers. Our explainer on card-linked offers and where brands fit covers how these schemes work. We compare the two approaches in more depth in Zeal compared with Fidel API.
App, QR and stamp-card loyalty
Paper stamp cards, loyalty apps and phone wallet passes all ask the customer to do something extra each visit: find the card, open the app or show a code. They work well for customers who remember. They also work for cash payments, which card-linked loyalty doesn't reach. We set out the wider argument in why app-free loyalty scales card-present customer data.
When another kind of loyalty is the better choice
- You want new customers from a bank's audience. Card-linked offers are built for reach across many cardholders.
- Most of your customers pay cash. A stamp card or app will reach more of them.
- You want ordering, booking and push messages. An app does more than loyalty. Zeal can power a branded app and connect it to your card machine, but the app is a bigger project than switching on card-linked loyalty.
How recognition works, without the jargon
When a customer pays by card, the card machine handles the payment as it always has. Card-linked loyalty software works alongside the payment app and uses a token for the card: a stand-in reference, not the card number itself. That token lets the system recognise a returning card. A token is a reference to a card, not a customer's name or contact details.
Zeal also offers optional phone-number capture: customers can share their number on the card machine and link it to their payment card token, which helps recognise return visits and build customer insight. For how this fits inside the payment itself, see card-linked loyalty inside the payment.
A note on phones. Apple says Apple Pay uses a "device-specific Device Account Number" and that neither Apple nor the device sends the actual card number. So a payment by phone can look different from a payment by the plastic card. Whether phone payments count on your setup depends on your card machine provider, so ask us to check yours before you tell customers.
Refunds and returns
Every loyalty programme needs a clear answer to "what happens to the points if they bring it back?". Card-linked offers set their own rules: American Express, for example, says in its offer terms that it may reverse the statement credit or rewards if a purchase is returned.
For card-linked loyalty on your own card machine, ask Zeal how refunds affect stamps and points on your setup, and make sure your in-store notice explains it.
Privacy: UK GDPR and PECR in plain words
Customers will reasonably ask what happens to their payment data. At a high level, with Zeal:
- A token, not the card number. Zeal works with a token for each card, not the card number itself.
- Recognition starts straight away. Zeal recognises returning cards from the moment it is switched on.
- Earlier visits can count. When a customer joins, their earlier visits on that card can be added to their account.
- It is still personal data. A token on its own isn't a name, but once it is linked to a loyalty account it counts as personal data under UK GDPR. The ICO explains this in its guidance on pseudonymisation, which it says is under review after the Data (Use and Access) Act.
- Responsibilities are shared. Zeal and each merchant are joint controllers for that merchant's programme. Zeal's joint controller arrangement sets out who does what, including the template wording Zeal provides for the notice you display where customers pay.
- Marketing needs its own permission. Joining is not agreement to marketing emails or texts. Under PECR, the UK's rules on electronic marketing, the ICO says organisations "normally must have consent before sending unsolicited electronic mail marketing to individual subscribers", unless every condition of the "soft opt-in" is met.
Customers can opt out at any time. Zeal's privacy policy explains how this works. This is a plain summary, not legal advice.
What you see as a merchant
The point of card-linked loyalty is not just rewarding regulars. It is finally seeing them. Because recognition comes from the card the customer pays with, the picture builds from your normal trade rather than from sign-up forms or stamp cards that get left at home.
With Zeal, that means knowing which customers are new and which are returning, and which offers actually brought people back. Each redemption is a real transaction, so the numbers describe visits and takings rather than clicks. That is information an owner can act on, for example knowing which afternoons are quiet and which regulars usually come in then.
Zeal is also clear about what it won't do. It won't bring back a customer who didn't enjoy the visit, because loyalty rewards intent that already exists (see why shoppers join loyalty schemes but don't return). And it builds at the speed of your trade: a quiet week is a quiet week for the programme too.
How to start
Zeal has 30,000+ merchants activated across payment providers in its markets. In the UK, it is live on card machines from Worldpay, Elavon, Lloyds Cardnet, NMI, Adyen, DNA Payments and Viva Wallet. Getting started looks like this:
- Check who provides your card machine and which model it is.
- Ask for Zeal to be switched on. Zeal confirms your setup first.
- Zeal starts recognising returning cards straight away. After the first month, it suggests a loyalty programme built from your own card payments.
- Choose your rewards: stamps or points.
Our step-by-step guide, how to link your card machine to a loyalty app, covers each step and what to do on every major UK provider, including those where you can Join the Waitlist and closed platforms. If you run a restaurant, see loyalty for restaurants. To check your own setup, talk to us.
Frequently asked questions
What is card-linked loyalty?
Card-linked loyalty is a loyalty programme where customers earn rewards from the payment card they already use. They join once, then later card payments count towards rewards, with no loyalty card, app or QR code to show.
Is card-linked loyalty the same as card-linked offers?
No. Card-linked offers are run by a bank, card company or cashback app: customers save an offer to their card in that service before they shop. Card-linked loyalty on your card machine is your own programme, in your brand, and customers join it when they pay with you.
Which card machines does card-linked loyalty work on?
With Zeal in the UK, it works on supported models from Worldpay, Elavon, Lloyds Cardnet, NMI, Adyen, DNA Payments and Viva Wallet, and Zeal checks your model before anything is switched on. For Barclaycard, Clover, Dojo, Global Payments, Tyl by NatWest and takepayments, Join the Waitlist and we'll tell you when Zeal is ready for your provider. Square, SumUp, Zettle, Stripe Terminal and Teya card machines can't host Zeal.
Does it work when customers pay with their phone?
It depends on your card machine provider. Ask us to check yours before you tell customers.
Is card-linked loyalty allowed under UK GDPR?
It can be, when it is set up properly. Once a card token is linked to a loyalty account it is personal data, so customers need a clear notice and a way to use their rights. With Zeal, responsibilities are shared under a joint controller arrangement, and marketing by email or text needs its own permission under PECR. This is not legal advice.
What happens to rewards when a customer gets a refund?
It depends on your setup. Ask Zeal how refunds affect stamps and points on your card machines, and make sure your in-store notice explains it.
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